Circuit breaker



Feb. 11, 1941.

J. G. JACKSON cmcum BREAKER Filed May 25, 1936,

,. 3 Sheet-Shet 1 INV ENT OR.

9 J25)? G J'acl'son.

ATTORNEY.

1941- JQG. JACKSON 2,231,072

' CIRCUIT BREAKER Filed May 23, 1936 3 Sheets-Sheet 2 INVENTOR.

ATTORNEY. I

Feb. 11,- 1941. J. G. JACKSON 2,231,072

CIRCUIT BREAKER Filed May 23, 1956 3 Sheets-Sheet 3 INVENTOR. J'bfii? 6.J'dcl'sa z ATTORNEY.

I Patented Feb. 1i; 1941 I t UNITED: STATES PATENTQOFFICEI omourrBREAKER John G. Jackson, Detroit, Mich, assignor to 1 Square D Company,Detroit, Mich, a corporation of Michigan Application May 23, 1936,Serial No, 81,369

14 Claims. (Cl. 200-168) This invention relates to devices for making ofstrap 5 is pivotally supported an operating and breaking electriccircuits and more particustrap 1. The end of the strap I remote from theiarly to electrical circuit breakers automatically exterior operati'n'ghandle to be hereinafter deoperable in response to current overload.scribed is provided with a flanged portion 8 hav- 5 One object of thepresent invention is the coning a slot therein through which projects aspring 5 version of a circuit breaker whose manual operguide 8 pivotallymounted on a rivet ll secured ation is normally dependent upon the speedof to the strap 5. A compression spring 12 -sur-' the operating handleinto an enclosed type of cir-' rounds the guide 9 and is compressedbetween cuit breaker wherein the speed of the operation flange 8 and'andrivet ll. At itsopposite end of the breaker mechanismwlll be independentof the strap I is rigidly secured to a pin i3 ex l0 the speed of theexterior handle. I tending through an opening in the strap 5 and Anotherobject 01 the invention a to provide a slot ill in the side wall, or thebox to the ,ex-

a quick make and break mechanism for an autoterior thereof. A stud 20threaded into the matic electric circuit breaker. strap 5 andtightenable against the side wall Another object of the presentinvention is to 0f h box i provided for maintaining e Strap 15 providean enclosed circuit breaker with quick within the-box interior. A platei4 rigid with make and break mechanism exterior of the cirthe strap 5may be provided: closely surrounding cuit breaker mechanism and withprovision for the pin l3 to provide a bearing therefor.

, indicating the automatically tripped condition of Keyed on the pin [3as by rivet i5 is an exthe breaker mechanism. terior operating portionl6. Pivotally mounted 20 Other objects and features of .the invention onthe pin 8 s an ope tin handle I? having a will be readily apparent tothose skilled in the uph p d P n fi p ra ins with the opart from thefollowing specifications and the crating portion to form an enclosurefor a torappended drawingsillustrating certain embodision spring I!which is disposed around a hub ments of the invention in which: 1 partof the operating portion It. The interior 2B Figure 1 is a frontelevational view of an era of the cup portion 18 on the handle i1 isDroclosed circuit breaker according to the present vided with aprojection 2| and the operating invention. portion has a pin 22 rigidtherewith and the Figure2isavertical sectional view taken onthe opp i ee of the torsion p in I9 are disso line n-n of Figure 1 with a portionbroken back posed at opposite sides or the pin 22 and e p oto show theover-center operating spring. 1 iection 2i.

Figure .3 is a horizontal sectional view taken on The handle I1 isprovided with a projection 23 the line III-.111 of Figure 1 with certainparts within a notch 24 in the operating portion l6. left in elevation.The projection 23 and the ends of the notch pro- Figure 4 is a verticalsectional view of the an vide for limited lost motion connection between35 cuit breaker mechanism taken on the line IV--IV the handle I1 and theoperating portion i6 and of Figure 3. V "for positive movement of theoperating portion Figure 5 is apartial sectional view showing the i8 bymeans of the handle when the projection. operating parts in manual "01!position. 23 engages the opposite ends of the notch.

40 Figure 6 is a partial sectional view showing Upon the supportingstrap 5 is mounted a clr- 4o 7 the operating parts in automaticallytripped pocuit breaker denoted generally at}! and corresitionn' spondingin general to that disclosed in appli- Figure '1 is a partial sectionalview showing the cant's copending application, Serial No. 64,575,operating parts in the resetting position. filed February 18, 1936, nowPatent No. 2,096,544. 4 Figure 8 is a detail sectional view or the hubThis circuit breaker may be 01 single or multiportion of the exterioroperating handle. pole type and has been here illustrated as a Figure 9is a sectional, view taken on the line three pole circuit breaker. Thecircuit breaker IX-4X oiFlgure 8. comprises a generally cup-shaped base28 hav- The circuit breaker according to the present ing a pair of walls21 dividing the base into three invention includes an exterior enclosingbox I- compartments for the individual poles of the 50 having a. cover 1provided with an opening 3 breaker. At one end or the base are provided1 closed by,a plate of glass or other transparent stationary contacts 28leading to terminal conmaterial 4. Within the box a generally U-shapednectors 29 at the exterior of the circuit breaker supporting plate 5 ishingedly mounted on the enclosure. Each pole is i'urther provided with65 sidewall as at 6. Upon the opposite side walls a floating contact bar3i having a contact mm face at one end cooperating with thecorresponding stationary contact 23 and latched at its opposite end to acommon latching member 32. The bars 3| are provided with notches 33 intheir upper edges received within the ends of slots 34 within operatingmembers 35. Light tension springs 35 bias the members 35 within thenotches 33 in the floating bars. Main operating springs 31 bias the barsagainst the stamovement thereof to move the contact bars 3|.

Individual bimetallic elements 4| are provided 1 mounted at one end onconnectors 42 leading to terminals 43 on the exterior of the breakerenclosure. Flexible leads interconnect the free ends of the bimetallicmembers 4| with the bars 3|. The latching element 32 comprisesindividual latches for the individual bars rigidly joined together'forcommon movement by any one'of the bimetallic members 4| in order torelease all the bars 3| in response to movement of any one. of thebimetals.4|. Spring strips 44 bias the main portion of the latchingelement' 32 away from the bimetallic members 4|. The opposite ends ofthe breaker are provided with fibre shields 45 and the enclosure iscompleted by atop cover 45 riveted or otherwise secured to the base. Alight spring 41 biases the handles 33-for rotation into engagement withthe mem-- bars 35 to secure an indicating position as hereinafterexplained. I

The operating strap 1 is provided with a wide slot 48 and within thisslot are disposed the operating handles 38 when thebreakerj is mountedon the strap 5. The handles have been shown as joined together by aU-shaped extension piece 43 to insure that the handleswill not slip outof the slot 48. An indicating stripe 5| is placed at the front of theextension 43. Thisextension piece is clamped on the handles by means ofstuds 52.

Upon the side wall of the box adjacent the over-center spring I2 aredisposed a rigid stop 53 for positively stopping the operating strap 1in the normal on" position of the parts and a resilient stop 54 forresiliently stopping the strap in the "ofi position of the parts. Theresilient stop includes a bracket 55 rigid with the side wall of the boxand provided with a slot through which extends the guide or pin portion55 on the be joined together as shown by the extension 43 as they willhave common movement in any event by engagement with the strap 1.

The parts as shown in Figure 4 are in the normal operating position. Tomove the parts to o position the exterior operating handle is rotated ina downward direction whereupon the handle moves relatively to theoperating portion 15 It, thus placing the spring l3 under tension.

This continues until the extension 23 on the operating handle engagesthe corresponding end of the notch 24 in operating portion l5, whereuponthis portion is posltively moved by the handle. This movement also movesthe oper- Lil ating strap 1 which is rigidly connected to the operatingportion 16 through pin l3 and the compression spring I2 is moved towardits dead center position from the position shown in Figure 2. As thespring |2 approaches its dead center position the force necessary tomove it decreases very rapidly and the force stored inspring l9 throwsit through its dead center position whereupon the over-center spring l2conwith the spring is being again tensioned. to

throw the over-center spring l2 through its dead center positionwhereupon the parts will assume the position shown in Figures 2 and 4.

Upon. the passage of an overload current through any one of the.bimetals 4| the latching element 32 will be moved toward thecorresponding end of the circuit breakerenclosure whereupon the bars 3|will be released and will rotate about their engagement with operatingmembers 35 under the bias of the springs 31 into the position shown inFigure 6, which is the automatically tripped position. of the breaker.As the spring 41 is relatively weak, the operating members 35 in this.position have moved upwardly rotating the handles counterclockwise asshown.

This indicating position of the operating handle may be viewed from theexterior of the circuit breaker enclosure through the window at thefront of the cover and the automatically tripped condition of thecircuit breaker can be readily ascertained. This movement of theoperating handles is permitted by the-enlarged slot 48 in the operatingstrap I. To-make the visual indication of the tripped condition moreapparent indicia may be placed on the front cover in alignment with thestripe 5| in its on and tripped positions as shown in Figure 1.

To reset the circuit breaker mechanism after an automatic trip the.handle is rotated downwardly beyond its oil position, whereupon theparts assume the position shown in Figure 7. In this movement the strap1 must be positively moved against the resilient stop Btuntil theoperating handles 38 move beyond their "ofi position. In this movementthe contact ends of the bars 3| engage the bottoms of the arc chambersand thereafter rotate about their engagement withthe operating members35 until their latching ends pass beneath the latch portions on thelatching element 32. handle after this reset operation places the partsin normal "off" position as in Figure 5 and Release ,of the operating toagain place the circuit breaker in normal 0peratingposition the handleis moved upwardly as in normal manual operation.

It is seen that while the normal operation of the circuit breaker itselfis dependent upon the speed of operation of the handles 38, provision ishere made for providing quick make and break operation of the circuitbreaker mechanism in response-to the operation of the exterior handlewhile at the same time preserving automatic trip indication. Thisenables the rather simple circuit breaker mechanismshown to be usedwhere quick make and break operationis required without the necessity ofchanging to the expensive and complex. type of circuit breaker.

the drawing in of wires and, the attachment of.

a conduit.

It' is understood that in-its broad aspects applicants inventionincludes the use of any external quick make and break operatingmechanism with any type of circuit breaker and that while certainpreferred embodiments of the invention have been specifically disclosed,thelnvention is not limited thereto as many variations will bereadilyapparent to those skilled in the art and the invention is tobe-given its broadest possible interpretation within the terms of thefollowing claims:

I claim: 9

1. An electric circuit breaker comprising an outer enclosing box, acircuit breaker enclosure mounted within said box, automatic and manualelectric circuit breaker mechanism mounted within said enclosure andhaving operating means projecting through the enclosure, an operatinghandle on the exterior of said box, means operatively connecting saidhandle with said operating means, means for causing the movement oi!said operating means in response to movement or said handle to besnap-like in action, means forresiliently stopping said connecting meansin one direction to maintain said operating means in a normal position,saidhandle positively moving said connecting means against the bias ofsaid resilient meansto move said operating means to resetting positionafter handle on the exterior of said box, means operatively connectingsaid handles with said op-, crating means, means for causing themovement or said operating means in response to movement oi said handleto be snap-like in action, means for positively stopping said connectingmeans in one direction, and a resilient stop for said connecting meansin the opposite direction, said handle positively moving -'saidconnecting means against said resilient stop to effect movement of saidoperating means to resetting position.

3. An electric circuit breaker comprising an outer enclosingbox, acircuit breaker enclosure mounted wlthinsaid box, automatic and manualelectric circuit breaker mechanism mounted within said enclosure andhaving operating means projecting through the enclosure, an' operatinghandle on the exterior or said box, means operatively connecting saidhandle with said operating means and providing for limited -inde-.pendent movement or the operating means to a position indicatingautomatic operation of the a circuit breaker mechanism, and means movingsaid connecting means a snap action in response to movement of thehandle.

4. An electric circuit breaker comprising an outer enclosing box, acircuit breaker enclosure mounted within said box, automatic and man ualelectric circuit breaker mechanism mounted within said enclosure andhaving manual operating means therefor projecting through the enclosureand disposed within the box, an operating handle on the exterior of saidbox, means operatively connecting the handle at the exterior of the boxwith the operating means within the box, said last mentioned meansproviding for limited movement of the operating means independent of theexterior handle into an indicating position, said operating meansassuming said indicating position in response to an automatic operationof the circuit breaker mechanism, and a window in,said box adjacent tosaid operating means for disclosing said indicating position toinspection without the necessity of opening the box.

5. An electric circuit breaker comprising an outer enclosing box, acircuit breaker enclosure mounted within said box, automatic and manualelectric circuit breaker mechanism mounted within said enclosureandhaving operating means projecting through the enclosure, an operatingatively connecting said handle with said operating means and providingfor limited independent movement of the operating means, said operatingmeans assuming an indicating position in response to an automaticoperation of the circuit breaker, a window in said boxadjacent to saidoperating means for disclosing said'position, and means for causing themovement of saidoperating means in response to movement of said handleto be snap-like in action.

6. An electric circuit breaker comprising an handle on the exterior ofsaid box, means operouter enclosing box, a circuit breaker enclosuremounted within said box, automatic and manual electric circuit breakermechanism mounted within said enclosure and having operating meansprojecting through the enclosure, the speed of manual operation of saidmechanism being dependent on the speed or movement of said operating'means, an operating handle on the exterior of said box, and means formoving said operating means with a snap action in response t movement ofsaid exterior handle.

7. An electric circuit breaker comprising an outer enclosing box, ahinged supporting strap within said box, a circuit breaker enclosuremounted on said strap for swinging movement to the exterior of theenclosure, automatic and manual electric circuit breaker mechanismmounted within said enclosure and having op-' and a handle on theexterior of said box opera mounted within said enclosure and having operating means projecting through the enclosure, an operator pivotedonsaid strap and engaging'said operating means, oVer-centerspringjecting through the front of the enclosure, an

operating handle at theexterior of said outer enclosing box, and meansfor moving said operating means with a snap action in response tomovement of said exterior handle, irrespective of the speed of movementof the exterior handle.

10. Electric circuit breaker apparatus comprising anouter enclosing box,a complete unitary electric circuit breaker mounted within said box aand including an enclosure, automatic and manual electric circuitbreaker mechanism mounted within said enclosure andoperating meansprojecting through the front of the enclosure, the speed of manualoperation of said mechanism being dependent upon the speed of movementof said operating means, an'operating handle at the exterior of saidouter enclosing box, means operatively connecting said handle with saidoperating means, and means independent of said circuit breaker mechanismfor causing the movement of said operating means to be snap-like inaction in response to movement of said handle, irrespective of the speedof movement of the handle. I p I 11. Electric circuit breaker apparatuscomprising a complete unitary electric circuit breaker including anenclosure, automatic and manual electric circuit breaker mechanismmounted within said enclosure and having operating means projectingthrough the front of the enclosure, a second operatingmeans exterior tosaid enclosure, and means at the exterior of the enclosureinterconnecting said operating means and efiecting movement of saidfirst operating means with a snap-like action in response to movement ofsaid second operating means, irrespective of the speed of movement ofsaid second operating means.

,- means with a snap action in response to movement of said secondoperating means, irrespective of the speed of movement of said secondoperating means.

13. Electric circuit breaker apparatus comprising an outer enclosingbox, a complete unitary electric circuit breaker mounted within said boxand including anenclosure, automatic and manual electric circuit breakermechanism mounted within said enclosure and operating means projectingthrough the front of the enclosure, the speed of manual operation ofsaid mechanism being dependent upon the speed or movement of saidoperating means, an operating handle at the exterior of said outerenclosing box, means including a lost motion connection for connectingsaid exterior handle to said operating means, and an over-center springfor eflecting snap acting movement of said operating means in responseto movement of said exterior handle.

14. Electric circuit breaker apparatus comprising a complete unitaryelectric circuit breaker including an enclosure, automatic and manualelectric circuit breaker mechanism mounted within said enclosure andhaving operating means projecting through the front of the enclosure,the speed of manual operation of said mechanism being dependent upon thespeed of movement of said operating means, asecond operating meansexterior to said enclosure, means including a lost motion connection forconnecting said operating means, and an over-center spring for efiectingsnap acting movement of said first operating means in response tomovement of said second operating means.

JOHN G. JACKSON.

